When something is aesthetically pleasing it's beautiful and great to look at.
The saying of aesthetically pleasing is another way to say something is beautiful and great to look at or enjoyable to look at.
For example a natural waterfall on a mountain would be aesthetically pleasing to most anyone in the world who saw it.
There are some really great looking and aesthetically pleasing waterfalls and mountains in Arkansas and if you want to see really beautiful and aesthetically pleasing mountains and waterfalls you should go to Arkansas.
Pleasing means to give you joy for something or someone.
If something is not aesthetically pleasing then it can be an eyesore which means it's ugly and bad to look at.
A person can be aesthetically pleasing to someone who is attracted to that person.